In recent years, a vehicle equipped with a power storage device (for example, a secondary battery, a capacitor and the like) and running with driving force generated from the electric power stored in the power storage device has received attention as an environmentally-friendly vehicle. Such a vehicle includes, for example, an electric vehicle, a hybrid vehicle, a fuel-cell vehicle, and the like. There is a proposed technique for charging the power storage device mounted in the above-described vehicle by a commercial power supply having high power generation efficiency.
As a hybrid vehicle, there is also a known vehicle equipped with a power storage device that can be charged by a power supply external to the vehicle (hereinafter simply referred to as an “external power supply”) as in the case of the electric vehicle (which will be hereinafter simply referred to as “external charging”). For example, the so-called “plug-in hybrid vehicle” is known which is provided with a power storage device that can be charged by a household power supply through the charging cable connecting between the receptacle provided in the house and the charging port provided in the vehicle. According to this, an improvement in the fuel consumption efficiency of the hybrid vehicle can be expected.
As for such an externally chargeable vehicle, there has been developed a concept of supplying electric power from a vehicle, which is regarded as a power supply source, to a commonly-used electrical device external to the vehicle, as seen in the smart grid and the like. Furthermore, a vehicle may be used as a power supply for using an electrical device when working outdoors, in camping or the like.
Japanese Patent Laying-Open No. 2010-035277 (PTL 1) discloses a charging/discharging system capable of charging a battery mounted on a vehicle using a charging cable and supplying electric power from the vehicle to an electric load external to the vehicle by using a power cable exclusively for power feeding, which is different from the charging cable, and to which a power supply plug of the electric load external to the vehicle can be connected.